1. Field of the Invention
The present invention relates to a semiconductor device to be used as a TCP (tape carrier package), and to a fabrication method thereof.
2. Description of the Related Art
Conventionally, TCPs have served as a way of mounting semiconductor elements. In such a TCP, as shown in FIGS. 15, 16A and 16B, a quadrangular semiconductor element 112 is mounted from a rear side of a TCP tape carrier 116. At the semiconductor element 112, bumps 114 (electrodes) for electrical connection to the exterior are formed on unillustrated bonding pads. The TCP tape carrier 116 is constituted with a base film 118 (a tape-form member), inner leads 120 and a resist 122. The base film 118 is formed of polyimide or the like. The inner leads 120 are formed at a rear side of the base film 113 and electrically connect between the semiconductor element 112 and the bumps 114. The resist 122 is formed so as to protect the inner leads 120. A device hole 124 is provided in the base film 118 for checking and positioning a front surface of the semiconductor element 112 when the semiconductor element 112 is mounted at the base film 118. The inner leads 120 are formed in shapes such that distal end portions thereof protrude into the device hole 124. The distal end portions of the inner leads 120 are structured so as not to be fixed anywhere before bonding at the bumps 114 of the semiconductor element 112. Consequently, there are many cases in which problems of deformation of the distal end portions of the inner leads 120 occur due to heating at a time of bonding, external impacts and the like. Thus, there are problems in that reliable and accurate positioning with respect to the bumps 114 of the semiconductor element 112 cannot be maintained, yields are reduced, and connection failures occur.
In light of the above problems, Japanese Patent Application Laid-Open No. 11-40605 has proposed fixing distal end portions of inner leads to a polyimide film, to prevent deformation thereof. However, in this proposal, the inner leads are formed so as to traverse the device hole from both input sides and output sides, and the distal end portions thereof are fixed. Thus, there is a problem in that the inner leads cannot be formed densely, and the number of inner leads cannot be made large. This problem is important in view of the need to satisfy recent demands for high-level integration and miniaturization of semiconductor elements, and a solution is desired.
The present invention is provided to solve the above-described problems and a purpose is to achieve the following object. Specifically, an object of the present invention is to provide a semiconductor device in which a semiconductor element can be mounted with high reliability, high yield, and high levels of integration and miniaturization, and a fabrication method thereof.
The above purpose is satisfied by the following means. Specifically, a semiconductor device of the present invention is a semiconductor device including: a tape-form member including a first surface (rear surface) and a second surface (front surface); a semiconductor element mounted at the first surface of the tape-form member and including electrodes; and a plurality of inner leads formed at the second surface of the tape-form member and located at peripheral portions of the semiconductor element, the inner leads being electrically connected with the electrodes of the semiconductor element at the first surface of the tape form member, wherein an aperture for connection of the inner leads with the electrodes of the semiconductor element is formed in the tape-form member, the aperture for connection being formed at locations which do not coincide with locations of distal end portions of the inner leads, the distal end portions of the inner leads are fixed to the tape-form member, and the inner leads are electrically connected, through the aperture for connection from the first side of the tape-form member, with the electrodes of the semiconductor element.
In the semiconductor device of the present invention, it is suitable if the inner leads are formed at the second surface of the tape-form member and positioned at peripheral vicinity portions opposing the semiconductor element.
Further, the the aperture for connection may be formed in the tape-form member so as to be continuous substantially orthogonally to the inner leads, and the apertures for connection may be formed in the tape-form member in a one-to-one correspondence with the inner leads. When the apertures for connection are formed in the tape-form member in one-to-one correspondence with the inner leads, the inner leads and the electrodes of the semiconductor elements may be connected by a conductive adhesive.
Moreover, a device hole may be formed in the tape-form member and located at a central portion of the semiconductor element, the aperture for connection being formed at a peripheral vicinity of the device hole, or no device hole may be formed in the tape-form member.
According to a semiconductor device fabrication method of the present invention, a semiconductor device is provided with a semiconductor element mounted at a rear surface of a tape-form member and including electrodes, and a plurality of inner leads formed at a front surface of the tape-form member and located at peripheral portions of the semiconductor element, the inner leads being electrically connected with the electrodes of the semiconductor element at the rear surface of the tape form member. An aperture for connection of the inner leads with the electrodes of the semiconductor element is formed in the tape-form member, the aperture for connection being formed at locations which do not coincide with locations of distal end portions of the inner leads, the distal end portions of the inner leads are fixed to the tape-form member, and the inner leads are electrically connected, through the aperture for connection from the rear side of the tape-form member, with the electrodes of the semiconductor element.
In the semiconductor device of the present invention, inner leads are formed in the front surface of a tape-form member and located at peripheral portions of a semiconductor element that is to be mounted. The inner leads way be increased in number and may be formed at a closer pitch in accordance with the type of the semiconductor element that is to be mounted. Further, distal end portions of the inner leads are fixed at the tape-form member, and are connected to electrodes of the semiconductor element through a connection aperture. Consequently, problems with the distal end portions of the inner leads being deformed by heating during bonding, external impacts and the like are prevented. Thus, yield is increased with high reliability, and a highly integrated and miniaturized semiconductor element can be mounted.